Advanced Basic Procedure

Handheld Autorefractor Welch-Allyn SureSight Retinomax

SureSight – Important points make sure it is in the correct mode for “child” or “adult” Move the unit to lefft eye after to right eye measurements Remind the patient to look at the red light If confidence number is less than 6, retest eye Reprint if black boxes are on the printout. You can test a max of 3 times for each eye

Retinomax – Important points: Dimming lights may help obtain adequate confidence numbers If the confidence level is less than 8, retest eye A confidence level of “E” is not a valid reading It may help to put your thumb on pt forehead and place the forehead rest on your thumb instead of directly above the pt brow.

See handout for specific instuctions and recording.

Drop Instillation

Tono-pen In the ER, or with patients who are difficult to examine, we can check pressure using a handheld electronic Tono-pen.

Prepare patient by instilling a drop of topical anesthetic onto the eye Position patient in front of a fixation target Hold the tono-pen like you would a pencil Brace the heel of your hand on the patient’s cheek for stability while hold the unit perpendicular to and within ½ inch of the patient’s cornea

Depress operator button once Within 15 sec, Touch the unit to the cornea lightly and briefly, then withdraw. Repeat several times A chirp will sound and IOP measurement will sound After four valid reading are obtained, a final beep will sound and the average will appear

Calibration – [CAL] followed by row of dashes [----] – Point the tip straight down towards the floor – Hit operator’s button two times quickly – Wait 15 sec for the beep and the display {UP} – Then flip so the tip is directed to the ceiling – Display [Good] or [Bad]

oIuas&NR oIuas&NR

Extraocular muscles(EOM)

Check EOM in six positions of gaze: right, upper right, upper left, left, lower left, lower right. One eye muscle is the prime mover in each position of gaze.

Right gaze is mainly moved by the right lateral rectus muscle and the left medial rectus muscle. Upper right gaze is by the right superior rectus and left inferior oblique. Upper left gaze is by the left superior rectus and right inferior oblique. Left gaze is by the left lateral rectus and right medial rectus. Left lower gaze is by the left inferior rectus and right superior oblique. Right lower gaze is by the right inferior rectus and left superior oblique.

Check EOM motility by asking examinee to watch your light while keeping the head still, move your finger across in “H” pattern, at a distance about inches away from the examinee.

Confrontation Fields

Test peripheral vision – Sit about 3 ft directly in front the patient. – Ask patient to cover one eye while you close the opposite eye – Present varied number of fingers in each four quadrants while patient fixates on your nose

Pupils

To examine the pupils, the level of the ambient light should be reduced and, to relax accommodation, the patient should be directed to look at a distant object. Using a penlight directed from below, just barely illuminating the pupils, one inspects for symmetry in pupillary size. The patient continues to view a distant object, and each pupil is tested separately for constriction in response to bright light. Also, check the pupils with near-vision, as they should constrict with accommodation.

The penlight is then quickly moved from one pupil to the other, shining light directly into each eye (the "swinging penlight test" to elicit afferent pupillary defect) In this test, one is specifically looking for a pupil that dilates as the light is first directed toward it, demonstrating greater consensual than direct response. The afferent pupillary defect is also known as a Marcus Gunn pupil.

If any discrepancy of more than 1 mm in pupillary size is found, the pupils are measured in both bright and reduced ambient light. Differences in pupillary size (aniso-coria) tend to be physiologic and not pathologic if such differences are only 1 to 2 mm and remain the same in differing levels of ambient light.